ErrUnsupportedAlgorithm results from attempting to perform an operation that involves algorithms that are not currently implemented.
var ErrUnsupportedAlgorithm = errors.New("x509: cannot verify signature: algorithm unimplemented")
IncorrectPasswordError is returned when an incorrect password is detected.
var IncorrectPasswordError = errors.New("x509: decryption password incorrect")
func CreateCertificate(rand io.Reader, template, parent *Certificate, pub, priv interface{}) (cert []byte, err error)
CreateCertificate creates a new X.509v3 certificate based on a template. The following members of template are used: AuthorityKeyId, BasicConstraintsValid, DNSNames, ExcludedDNSDomains, ExtKeyUsage, IsCA, KeyUsage, MaxPathLen, MaxPathLenZero, NotAfter, NotBefore, PermittedDNSDomains, PermittedDNSDomainsCritical, SerialNumber, SignatureAlgorithm, Subject, SubjectKeyId, and UnknownExtKeyUsage.
The certificate is signed by parent. If parent is equal to template then the certificate is self-signed. The parameter pub is the public key of the signee and priv is the private key of the signer.
The returned slice is the certificate in DER encoding.
All keys types that are implemented via crypto.Signer are supported (This includes *rsa.PublicKey and *ecdsa.PublicKey.)
The AuthorityKeyId will be taken from the SubjectKeyId of parent, if any, unless the resulting certificate is self-signed. Otherwise the value from template will be used.
func CreateCertificateRequest(rand io.Reader, template *CertificateRequest, priv interface{}) (csr []byte, err error)
CreateCertificateRequest creates a new certificate request based on a template. The following members of template are used: Attributes, DNSNames, EmailAddresses, ExtraExtensions, IPAddresses, URIs, SignatureAlgorithm, and Subject. The private key is the private key of the signer.
The returned slice is the certificate request in DER encoding.
All keys types that are implemented via crypto.Signer are supported (This includes *rsa.PublicKey and *ecdsa.PublicKey.)
func DecryptPEMBlock(b *pem.Block, password []byte) ([]byte, error)
DecryptPEMBlock takes a password encrypted PEM block and the password used to encrypt it and returns a slice of decrypted DER encoded bytes. It inspects the DEK-Info header to determine the algorithm used for decryption. If no DEK-Info header is present, an error is returned. If an incorrect password is detected an IncorrectPasswordError is returned. Because of deficiencies in the encrypted-PEM format, it's not always possible to detect an incorrect password. In these cases no error will be returned but the decrypted DER bytes will be random noise.
func EncryptPEMBlock(rand io.Reader, blockType string, data, password []byte, alg PEMCipher) (*pem.Block, error)
EncryptPEMBlock returns a PEM block of the specified type holding the given DER-encoded data encrypted with the specified algorithm and password.
func IsEncryptedPEMBlock(b *pem.Block) bool
IsEncryptedPEMBlock returns if the PEM block is password encrypted.
func MarshalECPrivateKey(key *ecdsa.PrivateKey) ([]byte, error)
MarshalECPrivateKey marshals an EC private key into ASN.1, DER format.
func MarshalPKCS1PrivateKey(key *rsa.PrivateKey) []byte
MarshalPKCS1PrivateKey converts a private key to ASN.1 DER encoded form.
func MarshalPKCS1PublicKey(key *rsa.PublicKey) []byte
MarshalPKCS1PublicKey converts an RSA public key to PKCS#1, ASN.1 DER form.
func MarshalPKCS8PrivateKey(key interface{}) ([]byte, error)
MarshalPKCS8PrivateKey converts a private key to PKCS#8 encoded form. The following key types are supported: *rsa.PrivateKey, *ecdsa.PublicKey. Unsupported key types result in an error.
See RFC 5208.
func MarshalPKIXPublicKey(pub interface{}) ([]byte, error)
MarshalPKIXPublicKey serialises a public key to DER-encoded PKIX format.
func ParseCRL(crlBytes []byte) (*pkix.CertificateList, error)
ParseCRL parses a CRL from the given bytes. It's often the case that PEM encoded CRLs will appear where they should be DER encoded, so this function will transparently handle PEM encoding as long as there isn't any leading garbage.
func ParseCertificates(asn1Data []byte) ([]*Certificate, error)
ParseCertificates parses one or more certificates from the given ASN.1 DER data. The certificates must be concatenated with no intermediate padding.
func ParseDERCRL(derBytes []byte) (*pkix.CertificateList, error)
ParseDERCRL parses a DER encoded CRL from the given bytes.
func ParseECPrivateKey(der []byte) (*ecdsa.PrivateKey, error)
ParseECPrivateKey parses an ASN.1 Elliptic Curve Private Key Structure.
func ParsePKCS1PrivateKey(der []byte) (*rsa.PrivateKey, error)
ParsePKCS1PrivateKey returns an RSA private key from its ASN.1 PKCS#1 DER encoded form.
func ParsePKCS1PublicKey(der []byte) (*rsa.PublicKey, error)
ParsePKCS1PublicKey parses a PKCS#1 public key in ASN.1 DER form.
func ParsePKCS8PrivateKey(der []byte) (key interface{}, err error)
ParsePKCS8PrivateKey parses an unencrypted, PKCS#8 private key. See RFC 5208.
func ParsePKIXPublicKey(derBytes []byte) (pub interface{}, err error)
ParsePKIXPublicKey parses a DER encoded public key. These values are typically found in PEM blocks with "BEGIN PUBLIC KEY".
Supported key types include RSA, DSA, and ECDSA. Unknown key types result in an error.
On success, pub will be of type *rsa.PublicKey, *dsa.PublicKey, or *ecdsa.PublicKey.
▹ Example
CertPool is a set of certificates.
type CertPool struct {
// contains filtered or unexported fields
}
func NewCertPool() *CertPool
NewCertPool returns a new, empty CertPool.
func SystemCertPool() (*CertPool, error)
SystemCertPool returns a copy of the system cert pool.
Any mutations to the returned pool are not written to disk and do not affect any other pool.
func (s *CertPool) AddCert(cert *Certificate)
AddCert adds a certificate to a pool.
func (s *CertPool) AppendCertsFromPEM(pemCerts []byte) (ok bool)
AppendCertsFromPEM attempts to parse a series of PEM encoded certificates. It appends any certificates found to s and reports whether any certificates were successfully parsed.
On many Linux systems, /etc/ssl/cert.pem will contain the system wide set of root CAs in a format suitable for this function.
func (s *CertPool) Subjects() [][]byte
Subjects returns a list of the DER-encoded subjects of all of the certificates in the pool.
A Certificate represents an X.509 certificate.
type Certificate struct {
Raw []byte // Complete ASN.1 DER content (certificate, signature algorithm and signature).
RawTBSCertificate []byte // Certificate part of raw ASN.1 DER content.
RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
RawSubject []byte // DER encoded Subject
RawIssuer []byte // DER encoded Issuer
Signature []byte
SignatureAlgorithm SignatureAlgorithm
PublicKeyAlgorithm PublicKeyAlgorithm
PublicKey interface{}
Version int
SerialNumber *big.Int
Issuer pkix.Name
Subject pkix.Name
NotBefore, NotAfter time.Time // Validity bounds.
KeyUsage KeyUsage
// Extensions contains raw X.509 extensions. When parsing certificates,
// this can be used to extract non-critical extensions that are not
// parsed by this package. When marshaling certificates, the Extensions
// field is ignored, see ExtraExtensions.
Extensions []pkix.Extension
// ExtraExtensions contains extensions to be copied, raw, into any
// marshaled certificates. Values override any extensions that would
// otherwise be produced based on the other fields. The ExtraExtensions
// field is not populated when parsing certificates, see Extensions.
ExtraExtensions []pkix.Extension
// UnhandledCriticalExtensions contains a list of extension IDs that
// were not (fully) processed when parsing. Verify will fail if this
// slice is non-empty, unless verification is delegated to an OS
// library which understands all the critical extensions.
//
// Users can access these extensions using Extensions and can remove
// elements from this slice if they believe that they have been
// handled.
UnhandledCriticalExtensions []asn1.ObjectIdentifier
ExtKeyUsage []ExtKeyUsage // Sequence of extended key usages.
UnknownExtKeyUsage []asn1.ObjectIdentifier // Encountered extended key usages unknown to this package.
// BasicConstraintsValid indicates whether IsCA, MaxPathLen,
// and MaxPathLenZero are valid.
BasicConstraintsValid bool
IsCA bool
// MaxPathLen and MaxPathLenZero indicate the presence and
// value of the BasicConstraints' "pathLenConstraint".
//
// When parsing a certificate, a positive non-zero MaxPathLen
// means that the field was specified, -1 means it was unset,
// and MaxPathLenZero being true mean that the field was
// explicitly set to zero. The case of MaxPathLen==0 with MaxPathLenZero==false
// should be treated equivalent to -1 (unset).
//
// When generating a certificate, an unset pathLenConstraint
// can be requested with either MaxPathLen == -1 or using the
// zero value for both MaxPathLen and MaxPathLenZero.
MaxPathLen int
// MaxPathLenZero indicates that BasicConstraintsValid==true
// and MaxPathLen==0 should be interpreted as an actual
// maximum path length of zero. Otherwise, that combination is
// interpreted as MaxPathLen not being set.
MaxPathLenZero bool
SubjectKeyId []byte
AuthorityKeyId []byte
// RFC 5280, 4.2.2.1 (Authority Information Access)
OCSPServer []string
IssuingCertificateURL []string
// Subject Alternate Name values
DNSNames []string
EmailAddresses []string
IPAddresses []net.IP
URIs []*url.URL
// Name constraints
PermittedDNSDomainsCritical bool // if true then the name constraints are marked critical.
PermittedDNSDomains []string
ExcludedDNSDomains []string
PermittedIPRanges []*net.IPNet
ExcludedIPRanges []*net.IPNet
PermittedEmailAddresses []string
ExcludedEmailAddresses []string
PermittedURIDomains []string
ExcludedURIDomains []string
// CRL Distribution Points
CRLDistributionPoints []string
PolicyIdentifiers []asn1.ObjectIdentifier
}
func ParseCertificate(asn1Data []byte) (*Certificate, error)
ParseCertificate parses a single certificate from the given ASN.1 DER data.
func (c *Certificate) CheckCRLSignature(crl *pkix.CertificateList) error
CheckCRLSignature checks that the signature in crl is from c.
func (c *Certificate) CheckSignature(algo SignatureAlgorithm, signed, signature []byte) error
CheckSignature verifies that signature is a valid signature over signed from c's public key.
func (c *Certificate) CheckSignatureFrom(parent *Certificate) error
CheckSignatureFrom verifies that the signature on c is a valid signature from parent.
func (c *Certificate) CreateCRL(rand io.Reader, priv interface{}, revokedCerts []pkix.RevokedCertificate, now, expiry time.Time) (crlBytes []byte, err error)
CreateCRL returns a DER encoded CRL, signed by this Certificate, that contains the given list of revoked certificates.
func (c *Certificate) Equal(other *Certificate) bool
func (c *Certificate) Verify(opts VerifyOptions) (chains [][]*Certificate, err error)
Verify attempts to verify c by building one or more chains from c to a certificate in opts.Roots, using certificates in opts.Intermediates if needed. If successful, it returns one or more chains where the first element of the chain is c and the last element is from opts.Roots.
If opts.Roots is nil and system roots are unavailable the returned error will be of type SystemRootsError.
Name constraints in the intermediates will be applied to all names claimed in the chain, not just opts.DNSName. Thus it is invalid for a leaf to claim example.com if an intermediate doesn't permit it, even if example.com is not the name being validated. Note that DirectoryName constraints are not supported.
Extended Key Usage values are enforced down a chain, so an intermediate or root that enumerates EKUs prevents a leaf from asserting an EKU not in that list.
WARNING: this function doesn't do any revocation checking.
▹ Example
func (c *Certificate) VerifyHostname(h string) error
VerifyHostname returns nil if c is a valid certificate for the named host. Otherwise it returns an error describing the mismatch.
CertificateInvalidError results when an odd error occurs. Users of this library probably want to handle all these errors uniformly.
type CertificateInvalidError struct {
Cert *Certificate
Reason InvalidReason
Detail string
}
func (e CertificateInvalidError) Error() string
CertificateRequest represents a PKCS #10, certificate signature request.
type CertificateRequest struct {
Raw []byte // Complete ASN.1 DER content (CSR, signature algorithm and signature).
RawTBSCertificateRequest []byte // Certificate request info part of raw ASN.1 DER content.
RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
RawSubject []byte // DER encoded Subject.
Version int
Signature []byte
SignatureAlgorithm SignatureAlgorithm
PublicKeyAlgorithm PublicKeyAlgorithm
PublicKey interface{}
Subject pkix.Name
// Attributes is the dried husk of a bug and shouldn't be used.
Attributes []pkix.AttributeTypeAndValueSET
// Extensions contains raw X.509 extensions. When parsing CSRs, this
// can be used to extract extensions that are not parsed by this
// package.
Extensions []pkix.Extension
// ExtraExtensions contains extensions to be copied, raw, into any
// marshaled CSR. Values override any extensions that would otherwise
// be produced based on the other fields but are overridden by any
// extensions specified in Attributes.
//
// The ExtraExtensions field is not populated when parsing CSRs, see
// Extensions.
ExtraExtensions []pkix.Extension
// Subject Alternate Name values.
DNSNames []string
EmailAddresses []string
IPAddresses []net.IP
URIs []*url.URL
}
func ParseCertificateRequest(asn1Data []byte) (*CertificateRequest, error)
ParseCertificateRequest parses a single certificate request from the given ASN.1 DER data.
func (c *CertificateRequest) CheckSignature() error
CheckSignature reports whether the signature on c is valid.
ConstraintViolationError results when a requested usage is not permitted by a certificate. For example: checking a signature when the public key isn't a certificate signing key.
type ConstraintViolationError struct{}
func (ConstraintViolationError) Error() string
ExtKeyUsage represents an extended set of actions that are valid for a given key. Each of the ExtKeyUsage* constants define a unique action.
type ExtKeyUsage int
const (
ExtKeyUsageAny ExtKeyUsage = iota
ExtKeyUsageServerAuth
ExtKeyUsageClientAuth
ExtKeyUsageCodeSigning
ExtKeyUsageEmailProtection
ExtKeyUsageIPSECEndSystem
ExtKeyUsageIPSECTunnel
ExtKeyUsageIPSECUser
ExtKeyUsageTimeStamping
ExtKeyUsageOCSPSigning
ExtKeyUsageMicrosoftServerGatedCrypto
ExtKeyUsageNetscapeServerGatedCrypto
ExtKeyUsageMicrosoftCommercialCodeSigning
ExtKeyUsageMicrosoftKernelCodeSigning
)
HostnameError results when the set of authorized names doesn't match the requested name.
type HostnameError struct {
Certificate *Certificate
Host string
}
func (h HostnameError) Error() string
An InsecureAlgorithmError
type InsecureAlgorithmError SignatureAlgorithm
func (e InsecureAlgorithmError) Error() string
type InvalidReason int
const (
// NotAuthorizedToSign results when a certificate is signed by another
// which isn't marked as a CA certificate.
NotAuthorizedToSign InvalidReason = iota
// Expired results when a certificate has expired, based on the time
// given in the VerifyOptions.
Expired
// CANotAuthorizedForThisName results when an intermediate or root
// certificate has a name constraint which doesn't permit a DNS or
// other name (including IP address) in the leaf certificate.
CANotAuthorizedForThisName
// TooManyIntermediates results when a path length constraint is
// violated.
TooManyIntermediates
// IncompatibleUsage results when the certificate's key usage indicates
// that it may only be used for a different purpose.
IncompatibleUsage
// NameMismatch results when the subject name of a parent certificate
// does not match the issuer name in the child.
NameMismatch
// NameConstraintsWithoutSANs results when a leaf certificate doesn't
// contain a Subject Alternative Name extension, but a CA certificate
// contains name constraints.
NameConstraintsWithoutSANs
// UnconstrainedName results when a CA certificate contains permitted
// name constraints, but leaf certificate contains a name of an
// unsupported or unconstrained type.
UnconstrainedName
// TooManyConstraints results when the number of comparision operations
// needed to check a certificate exceeds the limit set by
// VerifyOptions.MaxConstraintComparisions. This limit exists to
// prevent pathological certificates can consuming excessive amounts of
// CPU time to verify.
TooManyConstraints
// CANotAuthorizedForExtKeyUsage results when an intermediate or root
// certificate does not permit an extended key usage that is claimed by
// the leaf certificate.
CANotAuthorizedForExtKeyUsage
)
KeyUsage represents the set of actions that are valid for a given key. It's a bitmap of the KeyUsage* constants.
type KeyUsage int
const (
KeyUsageDigitalSignature KeyUsage = 1 << iota
KeyUsageContentCommitment
KeyUsageKeyEncipherment
KeyUsageDataEncipherment
KeyUsageKeyAgreement
KeyUsageCertSign
KeyUsageCRLSign
KeyUsageEncipherOnly
KeyUsageDecipherOnly
)
type PEMCipher int
Possible values for the EncryptPEMBlock encryption algorithm.
const (
PEMCipherDES PEMCipher
PEMCipher3DES
PEMCipherAES128
PEMCipherAES192
PEMCipherAES256
)
type PublicKeyAlgorithm int
const (
UnknownPublicKeyAlgorithm PublicKeyAlgorithm = iota
RSA
DSA
ECDSA
)
func (algo PublicKeyAlgorithm) String() string
type SignatureAlgorithm int
const (
UnknownSignatureAlgorithm SignatureAlgorithm = iota
MD2WithRSA
MD5WithRSA
SHA1WithRSA
SHA256WithRSA
SHA384WithRSA
SHA512WithRSA
DSAWithSHA1
DSAWithSHA256
ECDSAWithSHA1
ECDSAWithSHA256
ECDSAWithSHA384
ECDSAWithSHA512
SHA256WithRSAPSS
SHA384WithRSAPSS
SHA512WithRSAPSS
)
func (algo SignatureAlgorithm) String() string
SystemRootsError results when we fail to load the system root certificates.
type SystemRootsError struct {
Err error
}
func (se SystemRootsError) Error() string
type UnhandledCriticalExtension struct{}
func (h UnhandledCriticalExtension) Error() string
UnknownAuthorityError results when the certificate issuer is unknown
type UnknownAuthorityError struct {
Cert *Certificate
// contains filtered or unexported fields
}
func (e UnknownAuthorityError) Error() string
VerifyOptions contains parameters for Certificate.Verify. It's a structure because other PKIX verification APIs have ended up needing many options.
type VerifyOptions struct {
DNSName string
Intermediates *CertPool
Roots *CertPool // if nil, the system roots are used
CurrentTime time.Time // if zero, the current time is used
// KeyUsage specifies which Extended Key Usage values are acceptable.
// An empty list means ExtKeyUsageServerAuth. Key usage is considered a
// constraint down the chain which mirrors Windows CryptoAPI behavior,
// but not the spec. To accept any key usage, include ExtKeyUsageAny.
KeyUsages []ExtKeyUsage
// MaxConstraintComparisions is the maximum number of comparisons to
// perform when checking a given certificate's name constraints. If
// zero, a sensible default is used. This limit prevents pathalogical
// certificates from consuming excessive amounts of CPU time when
// validating.
MaxConstraintComparisions int
}